1. Field of the Invention
The invention relates to a device for orientating loads on a linear conveyor, as well as to an application of the device to a palletizer. It will find an application particularly with constructors of automatic handling equipment.
2. The Prior Art
Linear conveyors are very widely used in the industry for ensuring the transport of goods between different manufacturing stations. With new technological developments, an automated load gripping device is more and more frequently encountered at the end of the conveying chain. This is the case, for example, in boxing stations with palletizers which are installations designed to store loads such as, in particular, packages or boxes, on pallets.
In order for these automatic installations to function correctly, certain vital criteria have to be observed. In particular, the loads on the linear conveyor have to be correctly spaced and orientated. These two criteria are dictated by the work station located upstream of the linear conveyor on which the loads are actually placed. Here, we very often find automatic installations capable of working at given rate which dictates the interval between the packages and also, in accordance with geometrical output criteria, which necessitates a given position of the packages on the linear conveyor.
Generally, when the load is centered on the linear conveyor, and when a parallelepipedic object is involved, it is placed either transversely or longitudinally on the conveyor.
In certain applications, this fixed orientation of the load on the conveyor can be an impediment. For example, with automatic palletizers, it is necessary to place the load sometimes longitudinally and sometimes transversely on the pallet and, consequently, the package on the linear conveyor has to be in the desired position.
This alternative possibility is difficult to impose on the preceding work station and, consequently, use has to be made of a device for orientating the loads on the linear conveyor in order to place the package in the desired position.
At the present time, devices are known that are capable of orientating a load in a fixed position. This takes the form, for example, of a motorized lateral belt against which the package is pressed so that it bears against the belt and is correctly orientated.
However, when it is necessary to pivot the load through an angle of rotation of up to a quarter of a turn, the constructors offer few solutions.
One known solution consists in using a crossarm housed in the linear conveyor. The load is immobilized above the crossarm which is then raised, supporting the load, to disengage it from the rollers of the conveyor. The crossarm can then pivot to orentate the load and, once this operation has been accomplished, it is lowered again to retract into the rollers and leave the load to be moved on again, correctly orientated.
This device has three major defects. In the first place, there is an interruption in the continuous translation movement since the load is immobilized during its rotary movement. This considerably reduces the working rate of the linear conveyor.
Secondly, this technique can be applied only to loads of relatively small dimensions, low inertia and reasonable weight. In addition, the rotation is generally at least 90.degree..
Emphasis should also be placed on the costly nature of this mechanism, which uses a combination of different jacks.